Controllable coherent population transfers in superconducting qubits for quantum computing

TL;DR

This paper introduces a method using Stark-chirped rapid adiabatic passages (SCRAPs) for controllable, evolution-time insensitive population transfers in superconducting qubits, enabling elementary quantum logic gates and improved readout.

Contribution

It presents a novel approach employing SCRAPs for coherent control in superconducting qubits, compatible with existing Josephson devices, enhancing quantum gate operations and measurement.

Findings

Demonstrates population transfer in qubits using SCRAPs

Proposes implementation with existing Josephson phase qubits

Facilitates efficient qubit readout through adiabatic pulses

Abstract

We propose an approach to coherently transfer populations between selected quantum states in one- and two-qubit systems by using controllable Stark-chirped rapid adiabatic passages (SCRAPs). These {\it evolution-time insensitive} transfers, assisted by easily implementable single-qubit phase-shift operations, could serve as elementary logic gates for quantum computing. Specifically, this proposal could be conveniently demonstrated with existing Josephson phase qubits. Our proposal can find an immediate application in the readout of these qubits. Indeed, the broken parity symmetries of the bound states in these artificial "atoms" provide an efficient approach to design the required adiabatic pulses.